One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,3)(5,6)(7,11)(8,10)(9,12)(13,14)(15,20)(16,17)(18,27)(19,21)(22,25)(23,26)(24,28)(5,7)(6,9)(8,12)(10,11)(13,15)(14,20)(16,26)(17,23)(18,25)(19,24)(21,28)(22,27) involution — undirected(13,16,17,14,19,27,18,21)(15,22,23,28,24,26,25,20)(7,12)(9,11)(13,17,19,18)(14,16,21,27)(15,23,24,25)(20,26,28,22)(1,3,4,2)(6,10)(9,11)(15,24)(20,28)(22,26)(23,25)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.